
oh interesting I didn't think about that!
Basically I think "I feel dirty" means he feels extremely guilty about being very harmful to EH.
and as the comment above explains, it may be that at this specific instant he feels even worse because he may be pleased that EH is suffering so much / so scared that he doesn't wanna end the arrangement and has to still rely on TJ. Which means, TJ both feels bad for making EH suffer and is glad of EH needing TJ because EH is suffering. He dislikes hurting him AND enjoys the consequences of that hurting.
And that I think is a key element of the story even in the current chapters, where - rather than aiming for what is best for EH - he aims for EH to not leave him (early season 3 when he thinks to himself they must be together forever) even at the cost of still making him suffer, although he also hates seeing him suffer and thus tries to conciliate both goals. And that, is actually egoistic and could be very bad for EH. He helps EH to increase the chances of EH loving him and because he empathises, but that is for TJ's own sake and TJ does keep and extraordinary and unhealthy power advantage over EH in all kinds of way. The power relation is outstandingly unbalanced.

overall, the worst think in all that is the power imbalance.
Inequality is always a horrible thing, depriving the weaker one of their ability to make choices, forcing them into choosing between bad option and even worse options.
Debt is a bitch, capitalism is a bitch, EH not being protected by the law and social services from his childhood to his inherited debt is a shame to society.
TJ having so much power over EH is an even bigger problem that TJ's morals themselves.
hi guys im quite confuse what Taeju mean when he said "Father, I feel dirty. Much dirtier than I expected" in chapter 50. Can someone please explain what he means from that?